Wildfire smoke has been a persistent health threat across the Pacific Northwest throughout the 2026 fire season. From Portland to Spokane to Boise, residents have experienced multiple rounds of smoke-degraded air quality as one of the most active fire seasons in regional history burned millions of acres. With fire danger expected to remain elevated through the fall, understanding how to monitor and respond to smoke events is essential.

2026's Smoke Timeline

Oregon and Washington experienced some of the worst air quality in the nation at several points during the 2026 fire season:

  • Early August: Air quality advisories covered most of the Pacific Northwest following the explosive growth of fires near Spokane and eastern Oregon. Portland recorded air quality among the worst of any major city in the world for several days, with AQI reaching into the "Very Unhealthy" and "Hazardous" categories.
  • Mid-August: NASA satellite imagery captured the transport of smoke from Pacific Northwest wildfires across the entire continent, reaching the East Coast and Atlantic Ocean.
  • Late August / Early September: Air quality advisories were in effect for multiple Oregon counties including Clackamas, Multnomah, Washington, Baker, Crook, Deschutes, and Harney counties. The Oregon DEQ issued advisories noting conditions were expected to last through September 2.
  • Ongoing: Smoke from active fires including the Austin Fire in Mount Hood National Forest continues to affect air quality in the greater Portland metro area and surrounding Cascade foothills.

Understanding the Air Quality Index

The Air Quality Index (AQI) measures air pollution on a scale from 0 to 500. For wildfire smoke, the key pollutant is fine particulate matter (PM2.5) — tiny particles that penetrate deep into the lungs and bloodstream.

  • 0–50 (Good): No action needed for most people
  • 51–100 (Moderate): Unusually sensitive individuals should consider limiting prolonged outdoor exertion
  • 101–150 (Unhealthy for Sensitive Groups): Children, elderly, and those with respiratory or heart conditions should limit outdoor activity
  • 151–200 (Unhealthy): Everyone should limit prolonged outdoor exertion; sensitive groups should avoid it
  • 201–300 (Very Unhealthy): Everyone should avoid prolonged outdoor exertion
  • 301+ (Hazardous): Emergency conditions; everyone should remain indoors

Protecting Yourself During Smoke Events

  • Stay indoors with windows and doors closed during high smoke events
  • Use air purifiers with HEPA filters — especially in bedrooms and primary living areas
  • Wear an N95 or KN95 respirator if you must go outdoors; cloth masks do not filter fine particles
  • Run your HVAC system on recirculate rather than fresh air intake
  • Avoid vigorous exercise outdoors — physical exertion increases how deeply you breathe
  • Check on neighbors, the elderly, and children who may need assistance during extended smoke events

Monitoring Resources

  • AirNow.gov — Real-time AQI maps and forecasts nationwide
  • OregonSmoke.org — Oregon-specific smoke advisories and forecasts
  • WaSmoke.blogspot.com — Washington state smoke forecasting and monitoring
  • PurpleAir.com — Community sensor network for hyperlocal air quality readings
  • NWS Boise (weather.gov/boi) — Smoke forecast graphics for the Pacific Northwest

Sign up for local emergency alerts through your county emergency management office, as many Oregon and Washington counties now push smoke advisories through the same systems used for evacuation notices.